A tap changer with semiconductor switching elements, which is constructed as a hybrid switch, is known from WO 2001/022447. This known tap changer has, as hybrid switch, a mechanical part and an electrical part. The mechanical part, which is the actual subject of WO 2001/022447, has mechanical switching contacts in each of which a central part is a movable slide contact that is moved along a contact guide rail connected with the star point by a motor drive and in that case connects stationary contact elements. The actual load changeover itself is carried out by two IGBTs each with four diodes in a Graetz circuit. This known concept of a hybrid switch is subject to high mechanical loading in order to ensure the necessary load changeover precisely at the zero transition of the load current.
A further IGBT switching device is known from WO 1997/005536 (U.S. Pat. No. 5,969,511), in which the taps of the regulating winding of a power transformer are connectable with a load shunt through a series circuit of two IGBTs. However, in this arrangement it is necessary to specially adapt the tap changer to the respective tapped transformer that is to be connected.